Someone finally checked the sky against the canvas: in mid-June 1889 the moon over Saint-Rémy should have been fat and waning, not the crescent Vincent painted. Astronomy as art history, which is the best kind of pedantry.

A spider with a spring-loaded silk trap tuned to a single prey species, the notoriously bad-tempered green tree ant. The lovely twist is that the ants may be goaded into setting it off themselves, which is the Roman ballista, reinvented by an arachnid.

Friction is the villain of every physics homework problem, which is why it is fun to read someone who studies it for a living make the case for it. Tribology underpins everything from bearings to brakes, and the essay takes it all the way out to the stars.

Every database person has met an indexer like Samuel Palmer, who classified stories by how they made him feel. It took decades before a reader noticed and wrote in. A short, perfect read about why metadata needs a schema.

Holst finished The Planets in 1918, a dozen years before Pluto turned up, so in 2000 Colin Matthews composed an eighth movement to complete the set. Six years later the IAU demoted the planet, leaving the music orbiting an awkward category of its own. Bad timing, as a sub-genre of musicology.

Tens of thousands of years ago someone in a German cave carved birds, which makes them birders of a sort. Aeon's short film uses the Hohle Fels finds to ask why our species thrived where Neanderthals faded, and suggests that making art was part of the answer. A quiet reminder that people have been looking hard at birds for a very long time.

Omni was where hard science, airbrushed space art, very questionable parapsychology and genuinely great short fiction shared a binding. Gibson's early stories ran there, which is reason enough to go digging. Settle in; this is a long afternoon of retro-futurism.

Most people buy their gas-discharge displays; this maker is coating the glass himself with a home sputtering rig. The first prototype glowed only inside the vacuum chamber and died once sealed, which is exactly the sort of honest failure that makes these projects worth following.

Strictly useless and completely delightful: decoding QR codes by hand, error correction and all. It is the same pleasure as reading a hex dump, and you come away understanding what the little squares are actually doing. The human-readable QR variant at the end is a fun twist.

Ken Shirriff is back at the die photos, this time walking through the 8087's add and subtract microcode line by line. Systems people will enjoy the two-pass normalisation scheme and the candid description of the special-case handling as spaghetti. It is a reminder that IEEE floating point was hard-won silicon before it was a standard.

Archaeology with a wagging tail. The clever detail is that hairless dogs lack certain teeth because of the same gene, so even bare bones can reveal the breed. The diet results suggest these pups were fed more like children than like the other dogs.

Every kernel hacker's archaeology dream: someone cleans out a room and finds a nine-track reel labelled with what may be the only surviving copy of Fourth Edition UNIX, the first one mostly rewritten in C. The story is worth it for the reminder of how much of our history lives on fragile media in forgotten cupboards.

Before anyone had a stored program, people were summing sine waves with pulleys and a wire to print a year of tides in under half an hour. It is a lovely piece of special-purpose hardware, and the American one, nicknamed Old Brass Brains, stayed in service into the 1960s.